Re: The file table of the ramdisk 'root' is full on ESXi 5.1

Check this post

VMware KB: ESXi 5.1 host becomes unresponsive when attempting a vMotion migration or a configuration change

It seems to be caused by SNMP using all available inodes.

I was unable to vmotion machines off this host, did the above regarding snmp and I am able to evacuate the VMs from this host, so I may update to update 1 which should curb this problem.